There seems to be a lot of concern about which of Agi and ArP is preferred come 3.2.2, and a lot of people are confused because they are seeing Rawr recommend Agi but others recommending ArP. There are posts about it in several of the other feral DPS threads as well, so here's a short summary.

1. In version 2.2.15, Rawr was updated to use the 3.2.2 value of ArP. This version of Rawr also had some changes to ArP proc handling. See: http://elitistjerks.com/f31/t21713-r...6/#post1378958
2. These two factors, plus other potential model bugs or changes, have led to ArP being seemingly undervalued.
3. in 2.2.16, Rawr is reverted back to the live ArP values. See: http://elitistjerks.com/f31/t21713-r...7/#post1386560
4. Despite Rawr 2.2.15's recommendations, other theorycrafting tools (Tossks, Simcraft, FbN) still show ArP to be the stronger stat for a typical T8+ geared cat come 3.2.2, especially with Grim Toll or Mjolnir Runestone. See discussion of the various tools beginning here: Feral questions?
5. Hardcapping ArP is currently a strong choice, but in 3.2.2 it will probably be best to return to softcapping with Runestone. See discussion beginning here: FeralbyNight (Cat & Bear simulation tool)

In closure: try 2.2.16. If you still do not get the results you expect, try disabling temporary buffs like Heroism, equipping an ArP set, checking ArP food, creating ArP gemming templates, and then running the optimizer. For me (4pT8; Grim Toll; 568 ArP w/food), 2.2.16 shows similar stat rankings to what I'd expect based on simulations and theorycraft for live:
ArP > Agi > Strength > Hit, Exp when not capped > Crit, Haste > AP

For a detailed exploration of the value and nature of ArP, spend some time reading the FbN thread:
FeralbyNight (Cat & Bear simulation tool)
Nightcrowler has created and posted a number of very informative graphs and tables based on simulations with FbN.

My personal tests seem to differ a bit from the ArP recommendations many are giving (in that they are overvaluing the stat). I think the model in RAWR is working under the assumption that if you get beyond `300 base ArP and are wearing one of the two ArP trinkets Agility is near equal in value.

Er, well, that's not really how Rawr works. The only "assumptions" it includes are DPS mechanics, the data you input, and the mathematical model of your DPS cycle. The relative "values" of ArP and Agi are outputs from those assumptions, not inputs with them.

The oft-quoted "300 ArP" number is from empirical tests with FbN circa 3.0 and is unrelated to Rawr's model. For comparison, in Rawr, I believe my fairly typical Naxx set "tipped" from Agi to ArP as the preferred gem around 400-450 ArP, but it's always 100% dependent on your specific gear set.

Agility's value in gear is a relatively linear thing. Agility gives a set amount of crit and a set amount of AP for every bit of Agility you have. As opposed to Armor Penetration whose value increases the more you have. At 0 Armor Pen for instance Agility is just much better. However once you have a given amount of armor pen (300 being the magic number in most gear sets pre 3.2.2) then you will find that it's value outweighs Agility. However at that point you will not see a drastically large increase in damage between Agility and Armor Pen. Reaching way past that point (up into soft cap values for instance) you will see a more clear damage increase and the argument of Armor Pen vs Agility becomes a lot more clear in favor of Armor Pen.

What do you think about 2pc. T8 (gloves+shoulders) and 2pc. T9(head+legs), I have to add that I have not got the hands yet, which drops in 10man version >.<. Rawr says that I have ~90DPS more than with 3pc. T9 (shoulders+legs+head). Another point is, you have more expertise, 24, so nearly capped; hit is the same with 255 rating.
I don't really know how strong 2pc. T8 is?! So I try to keep it, till I will get the gloves. (Assassinenhandschuhe der Sonnenhäscher - Gegenstände - World of Warcraft Datenbank von buffed.de)

There are no T8 wrists.

And next time, just link items with the wowhead button.

[Sunreaver Assassin's Gloves]
-,- I meant gloves. Dunno how I come on writsts. xD

Not exactly what I meant. ^^
I think 2T9 + randoms is better than 4T9, 5% crit on rip an furious bite is not so good, I think.
I meant 2T8 (shoulders+gloves) + 2T9 (head+legs) or 2T9. Hmpf it is different to describ,i gonna make 2 profiles (armory down atm -,-). xD
I know that hitcap isn't important, but if autoattack has the most dmg in my recount, why should it be bad. And hitcap also means, that you can look ahead, which style you are using next.^^

Profile1 (2T8+2T9): chardev.org v6 ~ a World of Warcraft character planner
vs.
Profile2 (3T9): chardev.org v6 ~ a World of Warcraft character planner (If nordend beasts drops the leather legs, I will change with T9)

So what is better?

First of all thanks for the awesome guide and the constructive discussion in the past 10 pages.

My question was about the following scenario: Let's say I have Mangle up on the target and for the sake of argument I have 5 CP and [Mjolnir Runestone] procs and I proceed to Rip. Does each tick on the duration of the entire Rip apply the increased ArP or does each tick check if [Mjolnir Runestone] is still active and does damage based on the ArP at that given moment?

Nope, Rip is bleeding damage, that means it is not afficted by armor, so your rip-damage is just supported by your attackpower. It does no matter how much armor a mob has, rip-ticks are always equal high. So you have to look at your ap proccs, When you proceed to Rip while you have an AP-procc and the ap-procc disappears, your rip-ticks are as high as with the ap you set it on the mob. So if you have less ap and want so refresh, it does not work, you have to wait till it is consumed.

First time post here, after a long time reading all the amazing threads, with endless useful information. Has helped me out so many times in the past. This one in particular has really helped been interesting.

I have a couple of questions to ask about my gear choices in recent days that I'm unsure of, and want some clarification.

I recently bought Death-warmed Belt, and fitted it with two 20AGI gems, and a 10AGI 15STAM gem. I checked it all out on Rawr beforehand and it said it would give me a significant DPS increase; which it has, to an extent. I'm just a little concerned that I lost a fairly considerable amount of both expertise and hit over Belt of the Twilight Assassin.

Since my DPS has gone up, it isn't too much of an issue, but I have noticed, while looking at possible upgrades in the future, that a lot of the gear doesn't have all too much expertise on it. I'm worried that I'll end up with barely any and will end up with a lot of dodged attacks. Would it be wise to go back to the Twilight Assassin belt to hold onto as much expertise as I can? Or to stick with what I have and... hope for the best?

Perhaps this post is in the wrong thread, and totally out of context for the thread in general, but I figured I could get the best feedback here.

A little bit more on topic, I have a question about my crit percentage:

Self buffed, I have 54%, but this hits 60% once my Idol procs and with BoK, which I have 9 times out of 10. Is there such a thing as too much crit? Had a discussion with a guildmate, and they were saying that because I'm over 50% crit, there isn't any point in adding more because the next best thing is to have 100% simply because the only thing better than 1 out of 2 hits critting is all hits critting. This sounds like a load of rubbish to me, but it got me thinking. Perhaps I would benefit more from ArP gems rather than the AGI ones? I only have 181 ArP so I was holding off on adding these gems until a bit later.

Any feedback is appreciated. Again, sorry if this is in the wrong thread.

EDIT: Been looking around the forum posts here, and found a lot of people saying STR > AGI. Is this still the case? Should I be gemming STR and not AGI? I don't want to lose my crit %, but if STR offers me more overall DPS then I guess I need to regem.